corrected big O for sorted in python

Author: TzeMingHo

Sprint-2/improve_with_precomputing/common_prefix/common_prefix.py

@@ -15,7 +15,7 @@ def find_longest_common_prefix(strings: List[str]):
             longest = common
     return longest
 # before changes, it was N^2, bacause it got a for loop inside a for loop
-# after changes, it is N + N. The first N for sorted, and another N for the loop.
+# after changes, it is NlogN + N. The NlogN is the worst case for sorted, and another N for the loop.
 
 def find_common_prefix(left: str, right: str) -> str:
     min_length = min(len(left), len(right))